Characteristics and dynamics of autolytic microscopic changes in myocardial structures after hanging

BACKGROUND: Establishing the duration of death is a main challenge in forensic medical examinations of the corpses of persons who died from various external influences. This problem has recently attracted the attention of several researchers in the field of forensic medicine worldwide, whose efforts have been focused on finding new approaches to solving this complex problem. However, to date, methods that allow establishing duration of death more accurately remains to be developed.

AIM: To identify the dynamics of autolytic changes in myocardial structures at different times after death from hanging, making it possible to establish duration of death.

MATERIALS AND METHODS: The histological structure of the myocardium from 132 corpses of persons who died of mechanical asphyxia by hanging was studied. The corpses were of 112 men and 20 women aged 18–61 years. The postmortem period ranged from 6–14 to 72–76 hours, with most deaths occurring at 6–8 hours (9.8%), 9–10 hours (9.1%), 11–12 hours (8.3%), and 13–16 hours (7.6%). Cases with other postmortem periods ranged from 6.8% to 3.8%. In the Zeravshan Valley in Uzbekistan, which includes the main territory of the republic, the hot season usually lasts 3.6 months, from May 27 to September 14, with a maximum average daily temperature of 28°C–32°C. The hottest month of the year in the region is July, with an average temperature of 42°C–45°C. The cold season lasts 3.5 months on average, from November 25 to March 4, with a minimum average daily temperature of 8°C–11°C. Based on this, they were divided into the following subgroups: those who died in conditions of relatively low ambient temperatures (–7... + 14°C; n=63), those who died in conditions of average temperatures (7°С–20°С; n=46), and those who died in conditions of high temperatures (not lower than 25°С–30°С; n=23). In addition to the external temperature, other factors were considered, such as humidity, pressure, wind speed, etc., information on which was obtained through the official website of the Uzhydromet center (https://ru.weatherspark.com).

RESULTS: Under high air temperature conditions, autolytic changes in cardiomyocytes appeared 9–10 hours after death from hanging; by 25–28 hours, an increase in the area of cell cytolysis was observed. Under average ambient temperature conditions, similar changes in cardiomyocytes were noted after 11–12 hours, and by 25–28 hours, cardiomyocyte shrinkage was determined. Under low temperature conditions, similar conditions were found at 13–14 and 25–28 hours. Pronounced destructive changes in vascular structures in high temperature conditions occurred within 19–20 hours after death. The perivascular space greatly expands during the postmortem period, and in average temperature conditions, such states are observed by 21–22 hours and after 23–24 hours in low temperature conditions. In high temperature conditions, autolysis in the vessels developed 11–12 hours after death from hanging. Furthermore, in average temperature conditions, these changes were observed after 13–14 hours and after 15–16 hours in low temperature conditions. Consequently, autolytic changes in the structures of blood vessels and intravascular contents of the myocardium develop at different times in the postmortem period, depending on the temperature conditions of the external environment.

CONCLUSION: Considering the results of the assessment of the degree of development of cadaveric phenomena and those of supravital reactions, the data provided can be used in forensic practice in establishing the age of death after hanging, depending on the temperature conditions of the dry arid zone.